In a manufacturing process of a semiconductor device, there is a step in which a peripheral part of a substrate of a semiconductor wafer etc. is polished (for example, see Patent document 1). This step is the step in which, needle-shaped projections, which are formed by adhesion of by-products formed during etching on the bevel part and edge part of the Si wafer and further interacting with a mask of the etching in RIE (Reactive Ion Etching) step to forma trench (deep trench) of a trench capacitor on the surface of an Si wafer, are polished and removed by a polishing tape provided with polishing abrasive grain etc. The needle-shaped projections must be removed as the projections broken at the time of transporting of the wafer etc. cause dusting, which leads to decrease in yield.
Methods for preventing fragments of wafer and particles derived from the abrasive grains in the polishing tape from dispersing and adhering onto the wafer surface at the time of polishing in the above-described process include the method in which a surface protection film of the positive resist etc. is formed in advance, and further pure water is supplied over the wafer during polishing to cover the positive resist surface with water, etc. However, there has been a problem that since the resist film consisting of resin, etc. shows hydrophobicity, water cannot cover the whole positive resist surface, and these particles adhere strongly onto the resist surface, which can hardly be removed even if the surface after polishing is cleaned physically.
Measures for this include a method for increasing the affinity between the resist film and water by imparting hydrophilicity to the positive resist surface employing a certain means. As the hydrophilization processing of the positive resist surface, though the method by plasma processing is known generally, this method has the problem that it needs to introduce an equipment for plasma processing, which leads to increase of the cost.
As another hydrophilization processing method of the positive resist film, for example, Patent document 2 discloses a method for increasing hydrophilicity wherein —OH group is provided by dropping pure water onto the positive resist surface for 5 minutes or more in the method for manufacturing an optical disc. However, this method has the problem that the hydrophilization processing is time-consuming, therefore the throughput is decreased.
Further, in the method for forming a resist pattern, for example, Patent document 3 discloses the method for increasing hydrophilicity in which TMAH (tetramethylammonium hydroxide), diethyl ethanolamine aqueous solution etc. are used as hydrophilization process agents which have an excellent wettability of a developer, and these hydrophilization process agents are supplied onto the positive resist surface for several minutes. However, this method also has the problem that the hydrophilization processing is time-consuming, therefore the throughput is decreased.
Further, Patent document 4 discloses the method for preventing particles from adhering onto the substrate surface in which, when polishing the periphery of a substrate to be processed, a coating of a surfactant or a water-soluble polymer agent is provided on the substrate surface by supplying a surfactant or a water-soluble polymer agent on the substrate surface in advance. However, in this method, since the surfactant and the water-soluble polymer is removed by supplying pure water onto the substrate surface, which leads to loss of the coating effect, it is necessary to supply the surfactant continuously or intermittently during polish processing, and a large amount of process liquid is thus necessary, which is not economical.
Though hydrophilization of the positive resist surface can be accomplished by slightly dissolving the surface with a common organic alkali solution such as TMAH, choline etc., in the technique wherein a process liquid is coated on the wafer surface while spinning the wafer by using a single-wafer apparatus, and the process liquid is extended to the whole wafer surface using the centrifugal force generated by spinning, there is a problem that hydrophilization is insufficient as the process liquid is not expanded uniformly to the whole wafer surface, because the above-described organic alkali solution has a high surface tension, therefore a large amount of the process liquid is necessary, and the solution shows inferior wet and expand properties. These problems are especially significant in the case of hydrophilizing the whole positive resist surface on the large-sized wafer of, such as, 200 mm, 300 mm, etc.
Moreover, in the manufacturing process of a semiconductor device, a problem is concerned that the pattern is destroyed by the interface tension between a positive resist pattern and a rinse liquid (for example, water) at the time of rinsing and drying in the development process with advancement of nano-patterning and higher aspect ratio.
Patent document 1: JP, A, 2004-241434
Patent document 2: JP, A, 9-212922
Patent document 3: JP, A, 9-106081
Patent document 4: JP, A, 2005-277050